Modeling of ultrasonic velocity and attenuation for concrete inspection: a review

A review of advances in modeling for concrete ultrasonic inspection is proposed. Various well-known (Non-Destructive Evaluation) NDE methods based on different principles are usually used to assess the integrity of concrete structures. Classical ultrasonic techniques usually exploit the coherent transmitted wave propagating through the concrete and can be classified as methods using linear acoustics. The multiple scattering approaches (both analytical and numerical) for modeling this coherent wave have been reviewed, as well as their existing validations. Such validations in two dimensions highlight the need to consider in modeling with a finer attention the correlation between scatterers and the actual dimensionality of the problem. The state of the art related to the influence in modeling of the Interfacial Transition Zone (ITZ) – the thin porous layer surrounding each aggregate – and of the porosity is also reviewed for the case of sound (undamaged) concrete. Finally, different perspectives of modeling strategies are discussed.